[Vitamin status of 11- to 17-year-old healthy adolescents. Data from a longitudinal study]

In order to find out whether any age- or sex-related changes in vitamin nutrition or if any vitamin deficiencies can be detected in apparently healthy school children, blood vitamins (A, B1, B2, B6, C, and E) were determined in 111 children (54 boys and 57 girls), who took part in a longitudinal nutritional program. Most of the adolescents were examined yearly 5 times every year and afterwards two years later; at the begin of the study their age was 11 years, at the end 17 years. The results of vitamin determinations show for the most parameters age dependent changes, levels for Vitamin A, B1, and B2 becoming higher with increasing age, for Vitamin C in contrast markedly unfavorable. Using the criteria for risk for deficiency from adults a comparatively high percentage of adolescents must be considered to be at risk for deficiency (up to 30% for Vitamin B6). As this study shows partly statistically significant correlations between growth and some vitamin levels (e.g., for Vitamin A and E), age and sex related criteria for the assessment of vitamin status in adolescents should be made available. The results in general show that also in apparently healthy school-children subclinical biochemical vitamin deficiencies can be detected. This fact however, should be taken in consideration in planing and providing guidelines for an optimal nutritional program in adolescence.